PORT-AU-PRINCE, Haiti (AP) — Haiti has taken a rare step to protect the endangered mangrove forests along its coastline, the Caribbean nation’s government announced Thursday.

The move could complicate U.S. efforts to build a port in a bay that contains a rare marine and mangrove-forest ecosystem east of the northern city of Cap-Haitien.

The administration of Haitian President Michel Martelly said in a statement Thursday that the decree approved by the Council of Ministers on Wednesday will ban construction, fishing and hunting in mangrove forests. People will be forbidden from cutting, selling or otherwise making use of the trees.

Environmental problems abound in Haiti. Only 2 percent of the country still has trees because of decades of deforestation, mostly caused by the longtime common practice of chopping down trees to make charcoal as an inexpensive source of fuel.

The U.S. government has allocated $170 million to build a port and a power plant to serve the recently constructed Caracol Industrial Park, a $300-million facility that is the United States’ biggest investment in Haiti since the 2010 earthquake.

An environmental impact study has been commissioned by the U.S. Agency for International Development before port construction can begin. In a written statement, agency spokeswoman Anna-Maija Mattila-Litvak declined to comment on the possible impact Haiti’s latest move could have on port plans until the environmental study has been completed. She said she did not have information about when the impact report would be finished.

The U.S. Government Accountability Office said in a report last month that the Caracol industrial park, the power plant and port are “interdependent” and that all of them must be constructed for the others to succeed. The same study also said that USAID needed to fill a vacant post for a port engineer, who will oversee port planning and construction.

In the meantime, another port in nearby Cap-Haitien doesn’t have the infrastructure to support Caracol, so supplies for the industrial park are now being shipped out of the neighboring Dominican Republic. The park’s main tenant, the South Korean manufacturing firm Sae-A Trading Co. Ltd., has already moved in and has begun work making T-shirts.